THE WORLD’S POPULATION is said to reach 7 billion today – and the birth of new babies has been celebrated all over the planet on this Monday.

In the Philippines, at two minutes before midnight a tiny, wrinkled girl was born into a struggling Manila family and became a symbol of the world’s population reaching 7 billion people and all the worries that entails for the planet’s future.

Danica May Camacho was welcomed with a chocolate cake marked “7B Philippines” and a gift certificate for free shoes.

Because of the millions of births and deaths around the world each day, it is impossible to pinpoint the arrival of the globe’s 7 billionth occupant.

But the UN chose Monday to mark the day with a string of festivities worldwide, and a series of symbolic 7-billionth babies being born.

Danica was the first, arriving at Manila’s Jose Fabella Memorial Hospital at two minutes before midnight Sunday — but doctors say that was close enough to count for a Monday birthday.

“She looks so lovely,” the mother, Camille Galura, whispered as she cradled her month-premature 2.5-kilo (5.5-pound) baby.

The baby was the second for Galura and her partner, Florante Camacho, a driver who supports the family on a tiny salary.

Dr Eric Tayag of the Philippines’ Department of Health said later that the birth came with a warning.

Seven billion is a number we should think about deeply.

We should really focus on the question of whether there will be food, clean water, shelter, education and a decent life for every child,” he said. “If the answer is ‘no,’ it would be better for people to look at easing this population explosion.

Demographers say it took until 1804 for the world to reach its first billion people, and a century more until it hit 2 billion in 1927.

The twentieth century, though, saw things begin to increase rapidly: 3 billion in 1959; 4 billion in 1974; 5 billion in 1987; 6 billion in 1998.

The UN estimates the world’s population will reach 8 billion by 2025 and 10 billion by 2083.

But the numbers could vary widely, depending on everything from life expectancy to access to birth control to infant mortality rates.

In Uttar Pradesh, India, officials said  they would be appointing 7 girls born today to symbolise the 7 billion.

India struggles with a deeply held preference for sons and a skewed sex ratio because of millions of aborted female foetuses, and  is using the day to highlight that issue.

“It would be a fitting moment if the 7 billionth baby is a girl born in rural India,” said Dr Madhu Gupta, an Uttar Pradesh gynaecologist.

It would help in bringing the global focus back on girls, who are subject to inequality and bias.

But charity Plan International says that in sub-Saharan Africa, an estimated 66 per cent of births are not registered.

The UNFPA’s recent State of the Population 2011 report says that the population of Africa will more than triple in the 21st century, and that another billion people are expected to be added in the next 35 years.

Plan International says that the lack of official birth registration has meant that children cannot sit exams in some countries and could be at risk of trafficking and child labour.

The United Nations Population Fund is encouraging people to make a world of 7 billion “a better place for all of us”.

It is collecting people’s individual stories from around the world via its website.

Meanwhile, TIME examines how the world’s population reached 7 billion, and the National Geographic Magazine asks ‘are you a typical person?

- Additional reporting by Associated Press

Column: An open letter to the world’s seven billionth child>